davis



A. F. H. DAVIS.

ELECTRIC SWITCH.

APPLICATION man Aus.22.,19|h

Patented Sept. 2,1919.

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ELECTIHG SWI'IUJEL ieiaiaa specification of Letters Patent.

Application filed August 2t, 1916. Ecrial No. mater.

To all whom it may concern:

Be it known that ABNER F. H. DAvIs, a

citizen of the United States, and residing at Oakland, in the county of Alameda and State of California, has invented certain new and useful Improvements in Electric Switches, ofwhich the following is a speciorder to reestablish the circuit it is necessary to set a number of dials to a given combination.

Still an ther object of my, invention is to provide switchmeans by which the combi; nation may be readily changed and in eneral to provide a system which will a see lutely prevent the establishment of a circuit tothe spark plugs without a knowledge of the proper setting of the various switch members.

With these and other objects in 'yiew, the invention consists in the novel. constructions; combination and arrangements of parts herein illustrated and more specifically pointed out in theappended claims;

Referring to the drawings forming a part of this specificationz- Figure 1 is a view of front elevation of a switch plate showing an arrangement of dials thereon for controlling the circuits of a lt-cylinder engine, I

Fig. 2 is a View in rear elevation of same, Fig. 3 is a View in rear elevation of one of the switch members,

Fig. 4: is a view in section through this switch member,

Fig. 5 is a diagrammatic view showing the manner in which the improved switch is connected between the source of electrical energy and the various spark plugs.

Referring to corresponding parts of the v several views by. the same numerals of reference, 1 denotes the switch plate on the back of which is mounted various switch members 2. These members may be of any preferred construction but as here illus trated consist of the disks of insulation 3 and 4 between. which is held a metallic dish 5. These various disks are held together by means of, screws 6 and they are provided with the alining openings 7, which openings Patented dept a, ra n have screw threads through the disks d and i 5. The contact studs are denoted by 8 and- 9; the former being the contact member by which a circuit is completed through the switch, while the latter is a blank contact. The contacts 8 are provided with the screw port1ons 10 which extend through disk 4 and engage the threads'ot plate 5, while the contacts 9 are provided with screws ll which only engage the insulating disk 4:. By this construction when it is desired to chan the combination of the device it is 0 y necessary to remove the screw '8 and one of the short screws 9 and interchange their position. This construction also prevents the combination being read by an inspection of the rear of the switch. The switch members 2 are attachedtothe rear of plate 1 in any referred manner and the whole contained in a suitable box or case to prevent access to the rear.

Throughthe center of each switch mem ber extends a shaft 12' which also extends through openings in plate 1 and is provided on the outside with an indicating arm 13 and a button 14 by which it may be turned. 'Onthe other side of the switchit is provided with a contact arm 15 held between a spring washer 16 and fastening means, such as a nut 17. Surrounding the shaft is a ring 18 having a radially extending arm 19, on the outer end ofwhich is a screw 20 serving as,

indicated at 24c. Conductors 95 and 2d errtend to the terminals of the 2-way switch 2? and these conductors may be provided lltlfl with suitable fuses 28. From the main I terminal of the 2-way switch a conductor 29 extends to the contact 8 of the first switch member from the opposite terminal of which the conductor 30 extends to one terminal of a second switch member, and from the oppo-' llltl site terminal of the latter a conductor 31 attends to the timer 32. Fromthe timer conductors 33 extend to one terminal of the same number of switch members, and from thei opposite terminals of each of these switbhsmember s conductors 34 extend to the various park plugs 35, which as usual are grounded, as indicated at 36.

The front of plate l'is provided with indicating characters 40, either numerals or letters, which are positioned in same angular relation as the contact studs on the switch members 2; thus, as illustrated in Fig. 1, reading across the top, then across the bottom row from left to right, the combination is, 1, 2, 8, 3, 4, 8. The arms in'Fig. 5 being shown diagrammatically in the same position. Thus the current from the magneto flows through conductor 25, switch 27, conductor 29to the first switch 2. Here it flows through the screw 8, the plate 5, shaft 12, member 19 of that switch to conductor 30. The circuit continues through this conductor to the next switch, 'fiowing through it in like manner and thence to the timer 32; from" this timer current flows throughthe various other switches, 2 corresponding in number to the cylinders of the engine and from each of these switches a conductor 34 leads to the spark plugs. Thus if the switch arms 15 of the switches to which the conductors 2-9 and 30 are not positioned on their respective contacts 8, a circuit is not completed to the timer. Even should the circuit be completed through these two switch members it would be further necessary to complete the circuit through two or more remaining switches in order to obtain sufiicient power to run the engine.

Q .While I have illustrated with eight points of. contact, it will be understood that a larger number may .be used,

thus greatly increasing the number of posswitch members limit myself to the construction shown in so far as the limit is implied to the scopeof the claims.

I claim as new and wish ters Patent:

1. An electrical switch comprising a dial plate, a plurality of switch members, each member comprising a' contact arm, a plurality of removable studs, a conducting disk, an insulating disk, one only of said studs engaging said conducting disk, a conducting arm in electrical connection with said contact ann and binding screws on said conducting disk and said conducting arm.

2; An electrical switch comprising a dial plate, a switch member, a plurality of contact studs mounted in said switch member,

to cover by Leta switch shaft, a contact arm on said shaft for wiping said studs, an indicating arm on said shaft in front of said dial plate, an operating button on said sh'aft, a conducting plate in said switch member, any one of said studs being interchangeable with any other of said studs and but one of said studs being engageable with said conductin late.

3. An electrical switch comprising a dial, a switch member, a shaft, an indicating arm on said shaft extending over said dial, a conducting late in said switch member, a plurality of contacts mounted on said switch member, a switch arm on said shaft adapted to wipe said contacts, any one of said contacts being interchangeable with any other of said contacts and but one of said studs being engageable with said plate.

fl. An electrical switch comprising a dial, two insulation disks and a conducting disk arranged between said -insulation disks, a shaft extending through said disks, an indicator on said shaft over said dial, the insul 'ating outer disk and the conducting disk being provided with screw holes arranged around said shaft, screw contacts screwing into all except one of the screw holes of said outer insulating disk, a screw contact screwing into the remaining screw hole of said outer disk and one of the screw holes of said conductor disk, and a wiper on said shaft adapted to wipe said contacts.

In testimony whereof I afiix my signature.

ABNER F. H. DAVIS. 

